I9I5] R' H. A. Flimmer 41 5 



deducted from the nitrogen contained in the bromine precipitate and 

 the residue is calculated as peptone. 



It will be interesting to have the views of the Meeting as to 

 whether this particular Separation has any practical Utility. 



When gelatine is present this is also precipitated by the bromine 

 and the amount as determined below will obviously have to be sub- 

 tracted from the total precipitate in order to arrive at the percentage 

 of albumoses and peptones. 



Gelatine. Five to twenty grammes are dissolved in hot water 

 and evaporated to dryness with sand. The dried mass is then ground 

 finely in a mortar, placed in a beaker, and washed four times with 

 ice-cold alcohol, about 50 c.c. of alcohol being used for each washing. 

 The alcohol is pumped through an asbestos filter surrounded with 

 ice. The sand is then extracted several times with ice-cold alcohol 

 and water, gradually decreasing the strength of the alcohol with each 

 extraction until the final washing-solution contains only 10 percent 

 of alcohol by weight. In all about 5-6 washings of about 50 c.c- 

 each are required. The gelatine in the beaker and on the asbestos 

 filter is then dissolved in boiling water and the nitrogen determined 

 in the usual manner. 



N X 5.44 = Gelatine. 



Creatine and Creatinine. A 10 percent Solution of the extract 

 in distilled water is first prepared. Several 10 c.c. quantities of this 

 Solution, representing i gramme of extract, are pipetted into small 

 beakers and to each 10 c.c. of normal hydrochloric acid are added; 

 the beakers are placed in an autoclave and heated for half an hour at 

 a temperature of 120° C. ; the whole of the creatine present is thus 

 converted into Creatinine. The conversion may also be carried out 

 by dissolving 10 grammes of the extract in a 100 c.c. flask in about 

 90 c.c. of one-third normal hydrochloric acid, heating in a boiling 

 water bath for 4 hours, allowing to cool and making up to 100 c.c. 

 Ten c.c. of this converted Solution, representing i gramme of extract, 

 are used for each colour experiment. 



Fifty milligrammes of pure crystallised creatine (which contains 

 one molecule of water of crystallization), are similarly converted 

 with hydrochloric acid and the Solution made up to 100 c.c. To the 

 Contents of one of the beakers, or to the Solution of one gramme of 



